INFLUENCE OF THE STRUCTURAL REARRANGEMENTS ON THE STRESS SENSITIVITY OF MAGNETOSTRICTION IN A CO-RICH AMORPHOUS ALLOY

One of the more striking features of nearly nonmagnetostrictive amorphous alloys is that their saturation magnetostriction lambda-decreases with the applied tensile stress at a rate of 10(-10) MPa-1. In the comparison of different models developed to account for this phenomenon, the experimental analysis of the dependence of the stress derivative of magnetostriction A on the thermal history of the samples has a singular significance. In particular, it is of great importance to determine whether A changes after annealing. The experiments presented in this work deal with the magnetostriction behavior in a sample of composition (Co0.95Fe0.5)80Si10B10 annealed at constant temperature for different annealing times, under applied stress. The measurements of the magnetostriction as well as its stress dependence, which were carried out by different experimental techniques, confirm that the absolute value of A decreases as the structural relaxation takes place.